This is a working overview of immunomodulatory peptide, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2025-09-27 and is reviewed periodically as new material appears.
Laboratory work indicates that the peptide acts on cells of both the innate and adaptive immune systems. Reported effects include signalling through Toll-like receptors on dendritic cells, enhanced T-cell maturation, and increased natural killer cell activity. These actions are described largely from cell-culture and animal experiments, and the precise receptor-level events remain incompletely defined. Studies in humans have generally measured immune markers rather than a single defined molecular target. The resulting picture remains partly descriptive.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Results across trials have been mixed, and several studies were small or conducted under differing protocols. Regulatory status varies by country, and the compound is not approved in every jurisdiction where it is studied. Evidence for any single indication should be read with attention to sample size and endpoint choice.
Thymosin alpha-1 is a 28-residue peptide first isolated from thymus tissue in the 1970s. It corresponds to the N-terminal portion of thymosin beta-4, from which it is cleaved in vivo. The peptide carries an acetyl group at its N-terminus, a modification that affects its charge and stability. Synthetic material produced by solid-phase peptide synthesis is chemically identical to the natural fragment and is the form used in research and clinical studies.
Thymosin alpha 1 was identified in 1977 as a component of thymosin fraction 5, a heterogeneous preparation used in early studies of thymic function. Investigators purified the active material and determined its amino acid sequence, which enabled chemical synthesis. Work in the following decades concentrated on T-cell maturation and immune reconstitution in animals and small human cohorts. Early preparations varied in composition, so results from that period are difficult to compare with studies using defined synthetic peptide.
Clinical research has examined the peptide in chronic hepatitis B and C, as a vaccine adjuvant, and in sepsis and oncology settings. Findings across trials are mixed; some report changes in selected immune markers, while others find no clear clinical benefit. Many studies are small and define outcomes differently, which limits comparison. Regulatory approval is confined to a few countries, and the compound is not an approved drug in the United States or most of Europe.
| Property | Value | Notes |
|---|---|---|
| Chemical class | Peptide | 28 amino acid residues |
| Molecular weight | Approximately 3108 Da | Depends on acetylation state |
| N-terminal modification | Acetylated | Affects charge and stability |
| Natural source | Fragment of thymosin beta-4 | Cleaved in vivo |
| Sequence length | 28 residues | Synthetic form matches natural |
Lyophilized material is typically treated as a hygroscopic solid that should be brought to room temperature before the container is opened, which limits condensation on the powder. Reconstitution is commonly done with sterile water or a buffered diluent, and gentle mixing is preferred over vigorous agitation to reduce foaming and surface adsorption. Because peptides can bind to plastic and glass, diluents containing a small amount of carrier protein are sometimes used in laboratory work. Working solutions are generally aliquoted and prepared fresh rather than subjected to repeated freezing and thawing.
Stability depends on temperature, pH, and the number of freeze-thaw events the sample has experienced. Freeze-dried material is commonly held at -20 °C or colder, while reconstituted liquid is kept cold and used within a short window. Extreme pH and prolonged light exposure can promote deamidation, oxidation, or aggregation, particularly at asparagine and methionine positions. Adsorption to container walls can lower the measured concentration of a dilute solution even when the peptide molecules themselves remain intact.
Identity and purity are usually assessed by reversed-phase high-performance liquid chromatography, which separates the target peptide from truncated or chemically modified byproducts. Mass spectrometry confirms the expected molecular mass and can indicate acetylation state or sequence errors. Amino acid analysis and peptide mapping supply complementary sequence-level information, while endotoxin testing is relevant for preparations intended for cell or animal work. Purity figures reported by suppliers refer to the method used and are not directly comparable across laboratories unless conditions are stated.
Thymosin alpha 1 is a short peptide first isolated from bovine thymus tissue in the early 1970s during fractionation work aimed at identifying factors that influence T cell development. It belongs to a family of acidic thymic peptides, and the original preparations contained several components that were later separated by chromatography. The compound is now produced synthetically rather than extracted from tissue, which removes batch variability tied to animal sourcing. Researchers describe it as an immunomodulatory peptide because laboratory studies show effects on several cell types of the innate and adaptive immune systems.
The molecule consists of 28 amino acid residues with an acetyl group attached to the N-terminal serine. Its sequence is acidic overall, with several glutamic and aspartic acid residues distributed along the chain and no cysteine, so disulfide bridges do not form. The peptide carries a net negative charge at physiological pH. Because the N-terminus is blocked, the intact molecule resists degradation by many aminopeptidases, which contributes to its stability in biological fluids.
Thymosin alpha-1 is a synthetic peptide of 28 amino acid residues that corresponds to a naturally occurring fragment first isolated from thymus tissue. Its chain is acetylated at the amino terminus, a modification that shields the peptide from rapid cleavage by aminopeptidases. The molecule carries a net negative charge at physiological pH and dissolves freely in water. Researchers classify it as an immune-modulating agent rather than a classical hormone, because it acts on several cell types of both the innate and the adaptive immune system.
The peptide was identified during work in the 1970s on thymosin fraction 5, a partially purified extract of calf thymus. Investigators separated that mixture and characterized individual components, one of which they named thymosin alpha-1. The same compound later received the international nonproprietary name thymalfasin. Commercial material is produced by solid-phase peptide synthesis rather than by extraction, so synthetic and natural forms share an identical sequence. Naming conventions vary across the literature, and readers should distinguish the alpha-1 peptide from other thymosins that have unrelated sequences and functions.
Early work on thymic extracts in the 1960s described a heat-stable acidic fraction containing many polypeptides. Separation of that mixture yielded individual components, and thymosin alpha-1 was named as one of them on the basis of assays for T-cell activity. The first preparations came from calf thymus, while subsequent research and clinical material has been chemically synthesized. Nomenclature in older papers is inconsistent, and the same peptide sometimes appears under different designations, which complicates literature searches.
Most published studies on thymosin alpha-1 report changes in immune measurements rather than clinical outcomes, and findings differ across designs and populations. Whether the peptide signals through one defined receptor or through several less specific interactions remains an open question. Its reported circulation half-life of a few hours complicates comparison of dosing schedules across trials. Mechanistic claims are frequently drawn from isolated cell cultures, and how far those results extend to whole organisms is unresolved.
Atypical chronic pain syndrome Body dysmorphic disorder (dysmorphic syndrome, dysmorphophobia) Brachioradial pruritus Bromidrosiphobia Complex regional pain syndrome (reflex sympathetic dystrophy) Congenital insensitivity to pain with anhidrosis Delusional parasitosis (delusions of parasitosis, Ekbom syndrome, monosymptomatic hypochondriacal psychosis) Dermatothlasia Dermatitis artefacta (factitious dermatitis, factitial dermatitis) Glossodynia (burning mouth syndrome, burning tongue, orodynia) Levator ani syndrome Malum perforans pedis (neurotrophic ulcer, perforating ulcer of the foot) Meralgia paresthetica (Roth–Bernhardt disease) Neurotic excoriations Notalgia paresthetica (hereditary localized pruritus, posterior pigmented pruritic patch, subscapular pruritus) Postencephalitic trophic ulcer Psychogenic pruritus Riley–Day syndrome (familial dysautonomia) Scalp dysesthesia Sciatic nerve injury Scrotodynia Syringomyelia (Morvan's disease) Traumatic neuroma (amputation neuroma) Trichotillomania (trichotillosis) Trigeminal neuralgia (tic douloureux) Trigeminal trophic lesion (trigeminal trophic syndrome) Vulvodynia (vestibulodynia)
== History == Reslizumab was initially developed by Chuan-Chu Chou at Schering-Plough and was previously known as SCH-55700. In 1993, Chou and his group at Schering-Plough were granted the patent for the design, cloning and expression of the reslizumab drug. Ception Therapeutics acquired the drug and continued its development under the name CTx55700. In 2010, Ception Therapeutics was acquired by Cephalon for $250 million and the drug continued under development under the codename CEP-38072. In 2011, Teva Pharmaceuticals acquired Cephalon for $6.8 billion and continued the development of reslizumab.
Hemmer (2026) interprets Pleistocene Feliopsis palaeojavanica from the Trinil site (Indonesia) as a member of a previously unrecognized pantherine lineage that also included Miocene Pachypanthera piriyai, and interprets the studied felids as possible specialized crocodile hunters. 26 purported subfossil tiger specimens from Japan are reinterpreted as cave lions by Sun et al. (2026), indicating that cave lions were the Panthera lineage that colonized Japan during the Pleistocene. Evidence from the study of genomes of cave lions living across a time series spanning over 100,000 years, indicating that cave and modern lions were distinct evolutionary lineages with independent histories, as well as indicative of extensive population connectivity of cave lions and indicative of interbreeding of modern lions (likely from southwestern Asia) with cave lions during the Late Pleistocene, is presented by Stanton et al. (2026). Gedman et al. (2026) perform phylogenetic analyses based on paleogenomes generated from ancient DNA found in two specimens of dire wolves and report that the dire wolf lineage diverged from other canids around 4.5 million years ago, prior to the split between the black-backed jackal and other members of the subtribe Canina. Admixture analyses of the dire wolves' paleogenomes indicate hybridization between the lineage that led to the subtribe Cerdocyonina and the sister lineage to gray wolves, coyotes and dholes.
Sources: en.wikipedia.org
== Sodium-23 == Sodium-23 is the sole natural isotope of sodium, with an atomic mass of 22.98976928. Because of this, sodium-23 is used in nuclear magnetic resonance in various research fields, including materials science and battery research. Sodium-23 relaxation has applications in studying cation-biomolecule interactions, intracellular and extracellular sodium, ion transport in batteries, and quantum information processing.
=== Methods to increase approval rate === There are many theories as to the causes of the low approval rate for cerebroprotectants, and many strategies have been suggested in publications to improve the chance of approval of drugs in development. The strategies that journals suggest to improve the chance of approval in clinical trials are outlined below:
=== Genetics === Two-thirds of families with a history of type 2 diabetes report more than one family member having MASLD. There is a higher risk of fibrosis for family members where someone was diagnosed with MASH. Asian populations are more susceptible to metabolic syndrome and MASLD than their Western counterparts. Hispanic persons have a higher prevalence of MASLD than white individuals, whereas the lowest prevalence is observed in black individuals. MASLD is twice as prevalent in men as in women, which might be explained by lower levels of estrogen in men. Genetic variations in two genes are associated with MASLD: non-synonymous single-nucleotide polymorphisms (SNPs) in PNPLA3 and TM6SF2. Both correlate with MASLD presence and severity, but their roles for diagnosis remain unclear. Although MASLD has a genetic component, the American Association for the Study of Liver Diseases (AASLD) does not recommend screening family members as there is not enough confirmation of heritability, although there is some evidence from familial aggregation and twin studies.
Sources: en.wikipedia.org
Scott Boatwright, Chief Executive Officer and Board member Adam Rymer, Chief Financial Officer Curt Garner, President, Chief Strategy and Technology Officer Ilene Eskenazi, Chief Legal and Human Resources Officer Jason Kidd, Chief Operating Officer Laurie Schalow, Chief Corporate Affairs Officer Kerry Bridges, Chief Food Safety Officer
Colonoscopy (or virtual colonoscopy) may be used if there is suspicion of colorectal cancer. Sigmoidoscopy may show ulceration of the rectal wall if solitary rectal ulcer syndrome is present. Examination under anesthesia. Colonic transit study may identify slow transit constipation, which may be a relative contra-indication for surgery. Anorectal physiology / function tests (anorectal manometry) may be needed if clinical examination does not give enough information. The recto-anal inhibitory reflex may be reduced in IRP. Endorectal ultrasound may be indicated. However, transperineal ultrasound and translabial ultrasound are not recommended as they are not reliable for identification of IRP. The internal anal sphincter may appear thickened on endoanal ultrasound. Barium enema. Urodynamic testing.
==== Other effects ==== If the carbon in freshwater is partly acquired from aged carbon, such as rocks, then the result will be a reduction in the 14C/12C ratio in the water. For example, rivers that pass over limestone, which is mostly composed of calcium carbonate, will acquire carbonate ions. Similarly, groundwater can contain carbon derived from the rocks through which it has passed. These rocks are usually so old that they no longer contain any measurable 14C, so this carbon lowers the 14C/12C ratio of the water it enters, which can lead to apparent ages of thousands of years for both the affected water and the plants and freshwater organisms that live in it. This is known as the hard water effect because it is often associated with calcium ions, which are characteristic of hard water; other sources of carbon such as humus can produce similar results, and can also reduce the apparent age if they are of more recent origin than the sample. The effect varies greatly and there is no general offset that can be applied; additional research is usually needed to determine the size of the offset, for example by comparing the radiocarbon age of deposited freshwater shells with associated organic material. Volcanic eruptions eject large amounts of carbon into the air. The carbon is of geological origin and has no detectable 14C, so the 14C/12C ratio near the volcano is depressed relative to surrounding areas. Dormant volcanoes can also emit aged carbon.
Sources: en.wikipedia.org
It corresponds to the first 28 amino acids of thymosin beta-4, a larger protein found in many tissues. The fragment is acetylated at its N-terminus and is produced synthetically for research and pharmaceutical use. Synthetic and natural forms share the same sequence.
It is usually described as an immunomodulatory peptide rather than a classical hormone. It does not travel to a single distant organ in the manner of an endocrine hormone. Classification varies across sources, and some texts group it with thymic peptides generally.
The broad outline involves immune cell activation, but the specific molecular steps remain under investigation. Different studies report effects on dendritic cells, T cells, and natural killer cells. No single receptor has been confirmed as the sole mediator.
Trials differ in patient population, dose schedule, background treatment, and the endpoints used to judge success. Many are small and single-center, so random variation can dominate the reported effects.